Data confidentiality is currently a major concern. It is clear that data in all their forms have intrinsic value that is often difficult to evaluate. Much of the wealth of a corporation or even a country resides in this growing volume of paper and electronic documents that condense its past, present, and even future activities. Paper documents that justified protection were hidden, concealed in locations that were made as difficult as possible to access. The spread of e-mail and electronic filing renews the problem and spurs a search for solutions to the problem.
Answers in this field are based on the concept of secret data being shared by a group of individuals at a given time. The processes implemented to date were based on simple operations that could be carried out on any device capable of elementary operations (binary addition, shifting, permutations, etc.).
The very nature of these processes implies lengthy and particularly painstaking design to build a machine whose logic is virtually error-free and whose errors are in any event never fatal. The confidentiality or secrecy of the data, on which all system security depends, would indeed be broken if the data transmitted between the devices were not kept secret, and this disclosure would then cause the security of the system to fail.
The design of effective protocols thus represents a particularly large investment in time and resources. Also, there is a relationship between maximum security and the quantity of information to be processed.